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1,3-Dicarbonyl compounds as phosphine-free ligands for Pd-catalyzed Heck and Suzuki reactions
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作者 Xin Cui Juan Li +1 位作者 Lei Liu Qing Xiang Guo 《Chinese Chemical Letters》 SCIE CAS CSCD 2007年第6期625-628,共4页
Some 1,3-dicarbonyl compounds (such as pentane-2,4-dione and 3-oxo-N-phenylbutanamide) were found to constitute highly efficient, yet low-priced and phosphine-free ligands for the Pd-catalyzed Heck and Suzuki reaction... Some 1,3-dicarbonyl compounds (such as pentane-2,4-dione and 3-oxo-N-phenylbutanamide) were found to constitute highly efficient, yet low-priced and phosphine-free ligands for the Pd-catalyzed Heck and Suzuki reactions of aryl bromides and iodides with very high turnover numbers (ca. 103–104). 展开更多
关键词 Palladium catalyst Suzuki reaction Heck reaction phosphine-free ligand
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Investigation on the Coordination Mode of IL-Supported Diols Used as Phosphine-Free Ligands for Palladium Catalyzed Heck Reaction 被引量:1
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作者 Yueqin Cai Gonghua Song Xiao Chen 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2013年第10期1250-1256,共7页
The coordination mode of IL-supported diols used as phosphine-free ligands for palladium catalyzed Heck reaction has been investigated by tuning their compositions. The difference in coordination of these IL-supported... The coordination mode of IL-supported diols used as phosphine-free ligands for palladium catalyzed Heck reaction has been investigated by tuning their compositions. The difference in coordination of these IL-supported diols with metal Pd in Heck reaction was related to the changes of the cation rings, leading to the different activities of Pd catalyst in the reaction. The experimental results indicated that the activities of Pd catalyst were affected mainly by n-electron density of the cation rings. Compared to pyridinium and piperidinium cations, imidazolium cations showed the best coordination to metal Pd. In the meantime, C-2 hydrogen and the length of alkyl side chains had impacts on the coordination as well. 展开更多
关键词 homogeneous catalysis ACYLATION Heck reaction phosphine-free ligands
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Proton‑Prompted Ligand Exchange to Achieve High‑Efficiency CsPbI_(3) Quantum Dot Light‑Emitting Diodes 被引量:1
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作者 Yanming Li Ming Deng +2 位作者 Xuanyu Zhang Lei Qian Chaoyu Xiang 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第6期53-62,共10页
CsPbI_(3)perovskite quantum dots(QDs)are ideal materials for the next generation of red light-emitting diodes.However,the low phase stability of CsPbI_(3)QDs and long-chain insulating capping ligands hinder the improv... CsPbI_(3)perovskite quantum dots(QDs)are ideal materials for the next generation of red light-emitting diodes.However,the low phase stability of CsPbI_(3)QDs and long-chain insulating capping ligands hinder the improvement of device performance.Traditional in-situ ligand replacement and ligand exchange after synthesis were often difficult to control.Here,we proposed a new ligand exchange strategy using a proton-prompted insitu exchange of short 5-aminopentanoic acid ligands with long-chain oleic acid and oleylamine ligands to obtain stable small-size CsPbI_(3)QDs.This exchange strategy maintained the size and morphology of CsPbI_(3)QDs and improved the optical properties and the conductivity of CsPbI_(3)QDs films.As a result,high-efficiency red QD-based light-emitting diodes with an emission wavelength of 645 nm demonstrated a record maximum external quantum efficiency of 24.45%and an operational half-life of 10.79 h. 展开更多
关键词 CsPbI_(3) perovskite quantum dots Light-emitting diodes ligand exchange Proton-prompted in-situ exchange
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Structure–performance relationship of Au nanoclusters in electrocatalysis:Metal core and ligand structure
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作者 Bowen Li Lianmei Kang +3 位作者 Yongfeng Lun Jinli Yu Shuqin Song Yi Wang 《Carbon Energy》 SCIE EI CAS CSCD 2024年第8期63-89,共27页
Remarkable progress has characterized the field of electrocatalysis in recent decades,driven in part by an enhanced comprehension of catalyst structures and mechanisms at the nanoscale.Atomically precise metal nanoclu... Remarkable progress has characterized the field of electrocatalysis in recent decades,driven in part by an enhanced comprehension of catalyst structures and mechanisms at the nanoscale.Atomically precise metal nanoclusters,serving as exemplary models,significantly expand the range of accessible structures through diverse cores and ligands,creating an exceptional platform for the investigation of catalytic reactions.Notably,ligand‐protected Au nanoclusters(NCs)with precisely defined core numbers offer a distinct advantage in elucidating the correlation between their specific structures and the reaction mechanisms in electrocatalysis.The strategic modulation of the fine microstructures of Au NCs presents crucial opportunities for tailoring their electrocatalytic performance across various reactions.This review delves into the profound structural effects of Au NC cores and ligands in electrocatalysis,elucidating their underlying mechanisms.A detailed exploration of the fundamentals of Au NCs,considering core and ligand structures,follows.Subsequently,the interaction between the core and ligand structures of Au NCs and their impact on electrocatalytic performance in diverse reactions are examined.Concluding the discourse,challenges and personal prospects are presented to guide the rational design of efficient electrocatalysts and advance electrocatalytic reactions. 展开更多
关键词 Au nanoclusters CORE electrocatalytic performance ligand STRUCTURES
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Transition metal coordination polymers with flexible dicarboxylate ligand:Synthesis,characterization,and photoluminescence property
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作者 CUI Peipei LI Xin +5 位作者 CHEN Yilin CHENG Zhilin GAO Feiyan GUO Xu YAN Wenning DENG Yuchen 《无机化学学报》 SCIE CAS CSCD 北大核心 2024年第11期2221-2231,共11页
Under solvothermal conditions,six new coordination polymers(CPs)[Mn(L)(phen)(H_(2)O)]_(n)(1),[Co(L)(phen)(H_(2)O)]_(n)(2),[Cu(L)(phen)(H_(2)O)]_(n)(3),[Zn_(2)(L)_(2)(phen)2(H_(2)O)]_(n)(4),[Zn(L)(phen)]_(n)(5),and[Cd(... Under solvothermal conditions,six new coordination polymers(CPs)[Mn(L)(phen)(H_(2)O)]_(n)(1),[Co(L)(phen)(H_(2)O)]_(n)(2),[Cu(L)(phen)(H_(2)O)]_(n)(3),[Zn_(2)(L)_(2)(phen)2(H_(2)O)]_(n)(4),[Zn(L)(phen)]_(n)(5),and[Cd(L)(phen)2]_(n)(6)were synthesized by reactions of dicarboxylate ligand 2,2'-(1,2-phenylenebis(methylene))bis(sulfanediyl)dinobutyric acid(H_(2)L)and 1,10-phenanthroline(phen)with the corresponding metal salts.Complexes 1-6 have been structurally characterized by single-crystal X-ray diffraction analyses,elemental analysis,IR,thermogravimetric analysis,and powder X-ray diffraction.The structures of 1-6 are 1D chains,which are further connected by hydrogen bonding interac-tions to form 3D supramolecular structures.Among them,1 and 2 are isomorphic with L2-of syn-conformation,while L2-shows anti-conformation in 3-6.In addition,the solid-state photoluminescence property of 4-6 was investigated. 展开更多
关键词 flexible dicarboxylate ligand coordination polymers hydrogen bonding interaction CONFORMATION photoluminescence property
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Ligand modulation of active center to promote lead-free Cs_(2)AgInCl_(6)photocatalytic CO_(2)reduction
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作者 Baofei Sun Wei Chen +10 位作者 Yanyi Huang Daofu Wu Heng Luo Faguang Kuang Hongmei Ran Yichen Liu Liqin Gao Jinchen Zhou Bo Gao Qiang Huang Xiaosheng Tang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第8期660-669,I0015,共11页
Metal halide perovskites(MHP)are potential candidates for the photocatalytic reduction of CO_(2)due to their long photogenerated carrier lifetime and charge diffusion length.However,the conventional long-chain ligand ... Metal halide perovskites(MHP)are potential candidates for the photocatalytic reduction of CO_(2)due to their long photogenerated carrier lifetime and charge diffusion length.However,the conventional long-chain ligand impedes the adsorption and activation of CO_(2)molecules in practical applications.Here,a ligand modulation technology is employed to enhance the photocatalytic CO_(2)reduction activity of lead-free Cs_(2)AgInCl_(6)microcrystals(MCs).The Cs_(2)AgInCl_(6)MCs passivated by Oleic acid(OLA)and Octanoic acid(OCA)are used for photocatalytic CO_(2)reduction.The results show that the surface defects and electronic properties of Cs_(2)AgInCl_(6)MCs can be adjusted through ligand modulation.Compared with the OLA-Cs_(2)AgInCl_(6),the OCA-Cs_(2)AgInCl_(6)catalyst demonstrated a significant improvement in the catalytic yield of CO and CH_(4).The CO and CH_(4)catalytic yields of OCA-Cs_(2)AgInCl_(6)reached 171.88 and34.15μmol g^(-1)h^(-1)which were 2.03 and 12.98 times higher than those of OLA-Cs_(2)AgInCl_(6),and the total electron consumption rate of OCA-Cs_(2)AgInCl_(6)was 615.2μmol g^(-1)h^(-1)which was 3.25 times higher than that of OLA-Cs_(2)AgInCl_(6).Furthermore,in situ diffuse reflectance infrared Fourier transform spectra revealed the enhancement of photocatalytic activity in Cs_(2)AgInCl_(6)MCs induced by ligand modulation.This study illustrates the potential of lead-free Cs_(2)AgInCl_(6)MCs for efficient photocatalytic CO_(2)reduction and provides a ligand modulation strategy for the active promotion of MHP photocatalysts. 展开更多
关键词 Surface ligand Photocatalysis CO_(2)reduction Lead-free perovskite Reactive mechanism
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Assessment of programmed death-ligand 1 expression in primary tumors and paired lymph node metastases of gastric adenocarcinoma
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作者 Brendha Cação Coimbra Marina Alessandra Pereira +4 位作者 Leonardo Cardili Venancio Avancini Ferreira Alves Evandro Sobroza de Mello Ulysses Ribeiro Jr Marcus Fernando Kodama Pertille Ramos 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第3期883-893,共11页
BACKGROUND Anti-programmed death-1/programmed death-ligand 1(PD-1/PD-L1)immuno-therapy has demonstrated promising results on gastric cancer(GC).However,PD-L1 can express differently between metastatic sites and primar... BACKGROUND Anti-programmed death-1/programmed death-ligand 1(PD-1/PD-L1)immuno-therapy has demonstrated promising results on gastric cancer(GC).However,PD-L1 can express differently between metastatic sites and primary tumors(PT).AIM To compare PD-L1 status in PT and matched lymph node metastases(LNM)of GC patients and to determine the correlation between the PD-L1 status and clinicopathological characteristics.METHODS We retrospectively reviewed 284 GC patients who underwent D2-gastrectomy.PD-L1 was evaluated by immunohistochemistry(clone SP142)using the com-bined positive score.All PD-L1+PT staged as pN+were also tested for PD-L1 expression in their LNM.PD-L1(-)GC with pN+served as the comparison group.RESULTS Among 284 GC patients included,45 had PD-L1+PT and 24 of them had pN+.For comparison,44 PD-L1(-)cases with pN+were included(sample loss of 4 cases).Of the PD-L1+PT,54.2%(13/24 cases)were also PD-L1+in the LNM.Regarding PD-L1(-)PT,9.1%(4/44)had PD-L1+in the LNM.The agreement between PT and LNM had a kappa value of 0.483.Larger tumor size and moderate/severe peritumoral inflammatory response were associated with PD-L1 positivity in both sites.There was no statistical difference in overall survival for PT and LNM according to the PD-L1 status(P=0.166 and P=0.837,respectively).CONCLUSION Intra-patient heterogeneity in PD-L1 expression was observed between the PT and matched LNM.This disagreement in PD-L1 status may emphasize the importance of considering different tumor sites for analyses to select patients for immunotherapy. 展开更多
关键词 Gastric cancer Lymph node Programmed death ligand 1 Stomach neoplasms IMMUNOHISTOCHEMISTRY METASTASIS
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C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 pathway as a therapeutic target and regulatory mechanism for spinal cord injury
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作者 Xiangzi Wang Xiaofei Niu +4 位作者 Yingkai Wang Yang Liu Cheng Yang Xuyi Chen Zhongquan Qi 《Neural Regeneration Research》 SCIE CAS 2025年第8期2231-2244,共14页
Spinal cord injury involves non-reversible damage to the central nervous system that is characterized by limited regenerative capacity and secondary inflammatory damage.The expression of the C-C motif chemokine ligand... Spinal cord injury involves non-reversible damage to the central nervous system that is characterized by limited regenerative capacity and secondary inflammatory damage.The expression of the C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 axis exhibits significant differences before and after injury.Recent studies have revealed that the C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 axis is closely associated with secondary inflammatory responses and the recruitment of immune cells following spinal cord injury,suggesting that this axis is a novel target and regulatory control point for treatment.This review comprehensively examines the therapeutic strategies targeting the C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 axis,along with the regenerative and repair mechanisms linking the axis to spinal cord injury.Additionally,we summarize the upstream and downstream inflammatory signaling pathways associated with spinal cord injury and the C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 axis.This review primarily elaborates on therapeutic strategies that target the C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 axis and the latest progress of research on antagonistic drugs,along with the approaches used to exploit new therapeutic targets within the C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 axis and the development of targeted drugs.Nevertheless,there are presently no clinical studies relating to spinal cord injury that are focusing on the C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 axis.This review aims to provide new ideas and therapeutic strategies for the future treatment of spinal cord injury. 展开更多
关键词 apoptosis C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 pathway C-C motif chemokine receptor 2 antagonists chemokine ligand 2 chemokine receptor 2 inflammation macrophage microglia spinal cord injury therapeutic method
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Efficacy of chemotherapy containing bevacizumab in patients with metastatic colorectal cancer according to programmed cell death ligand 1
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作者 Shin Woo Kang Sung Hee Lim +5 位作者 Min-Ji Kim Jeeyun Lee Young Suk Park Ho Yeong Lim Won Ki Kang Seung Tae Kim 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第8期3521-3528,共8页
BACKGROUND Bevacizumab,an anti-vascular endothelial growth factor(VEGF)monoclonal antibody,inhibits angiogenesis and reduces tumor growth.Serum VEGF-C,lactate dehydrogenase,and inflammatory markers have been reported ... BACKGROUND Bevacizumab,an anti-vascular endothelial growth factor(VEGF)monoclonal antibody,inhibits angiogenesis and reduces tumor growth.Serum VEGF-C,lactate dehydrogenase,and inflammatory markers have been reported as predictive markers related to bevacizumab treatment.Programmed cell death ligand 1(PD-L1)could act upon VEGF receptor 2 to induce cancer cell angiogenesis and metastasis.AIM To investigate the efficacy of bevacizumab-containing chemotherapy in patients with metastatic colorectal cancer(CRC)according to the expression of PD-L1.METHODS This analysis included CRC patients who received bevacizumab plus FOLFOX or FOLFIRI as first-line therapy between June 24,2014 and February 28,2022,at Samsung Medical Center(Seoul,South Korea).Analysis of patient data included evaluation of PD-L1 expression by the combined positive score(CPS).We analyzed the efficacy of bevacizumab according to PD-L1 expression status in patients with CRC.RESULTS A total of 124 patients was included in this analysis.Almost all patients were treated with bevacizumab plus FOLFIRI or FOLFOX as the first-line chemotherapy.While 77%of patients received FOLFOX,23%received FOLFIRI as backbone first-line chemotherapy.The numbers of patients with a PD-L1 CPS of 1 or more,5 or more,or 10 or more were 105(85%),64(52%),and 32(26%),respectively.The results showed no significant difference in progression-free survival(PFS)and overall survival(OS)with bevacizumab treatment between patients with PDL1 CPS less than 1 and those with PD-L1 CPS of 1 or more(PD-L1<1%vs PD-L1≥1%;PFS:P=0.93,OS:P=0.33),between patients with PD-L1 CPS less than 5 and of 5 or more(PD-L1<5%vs PD-L1≥5%;PFS:P=0.409,OS:P=0.746),and between patients with PD-L1 CPS less than 10 and of 10 or more(PD-L1<10%vs PD-L1≥10%;PFS:P=0.529,OS:P=0.568).CONCLUSION Chemotherapy containing bevacizumab can be considered as first-line therapy in metastatic CRC irrespective of PD-L1 expression. 展开更多
关键词 BEVACIZUMAB Colorectal cancer Programmed cell death ligand 1 expression First-line chemotherapy Metastatic colorectal cancer
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Syntheses,structures,and properties of three coordination polymers based on 5⁃ethylpyridine⁃2,3⁃dicarboxylic acid and N⁃containing ligands
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作者 TANG Long BIAN Yaxin +3 位作者 CHEN Luyuan HOU Xiangyang WANG Xiao WANG Jijiang 《无机化学学报》 SCIE CAS CSCD 北大核心 2024年第10期1975-1985,共11页
Three coordination polymers[Mn(epda)(2,2'⁃bipy)(H_(2)O)](1),[Mn(epda)(phen)](2),and[Co_(2)(epda)2(bpe)2(H_(2)O)_(4)]·5H_(2)O(3)(H2epda=5⁃ethyl⁃pyridine⁃2,3⁃dicarboxylic acid,2,2'⁃bipy=2,2'⁃bipyridine,... Three coordination polymers[Mn(epda)(2,2'⁃bipy)(H_(2)O)](1),[Mn(epda)(phen)](2),and[Co_(2)(epda)2(bpe)2(H_(2)O)_(4)]·5H_(2)O(3)(H2epda=5⁃ethyl⁃pyridine⁃2,3⁃dicarboxylic acid,2,2'⁃bipy=2,2'⁃bipyridine,phen=phenanthroline,bpe=1,2⁃bis(4⁃pyridyl)ethylene)were synthesized by solvothermal reactions and characterized by single⁃crystal X⁃ray diffraction,thermogravimetric analyses,IR spectroscopy and elemental analysis.1 displays a 1D chain struc⁃ture,and these chains are joined by O-H…O hydrogen bonding andπ⁃πstacking interactions to generate a 2D layer structure.2 displays a 2D layer structure,and adjacent layers are generated 3D architecture throughπ⁃πstacking interactions.3 displays a 1D chain structure,and adjacent chains are generated double layer structure through O-H…O hydrogen bonding.The fluorescent properties of 1 and 3 indicate that they can potentially be used as a luminescent sensor.1 was highly selective and sensitive towards o⁃nitrophenol through different detection mechanisms,however,3 was highly selective and sensitive towards 2,4,6⁃trinitrophenol.In addition,the magnetic behavior of 2 has also been investigated.CCDC:2172533,1,2355773,2,2355774,3. 展开更多
关键词 coordination polymers 5⁃ethyl⁃pyridine⁃2 3⁃dicarboxylate ligand crystal structures fluorescent properties magnetic behavior
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Comparative Study of the Efficacy of Metal Removal from Contaminated Aqueous Solutions by Solid Bidentate Ligands&Liquid Plant Materials
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作者 Lovell Agwaramgbo Talajai Sardin Christopher Alisa 《Journal of Environmental Science and Engineering(A)》 CAS 2024年第2期45-49,共5页
Heavy metal contaminated water sources pose serious health risks for humans,animals,and plants.Exposure to and ingestion of heavy metals have been associated to liver,kidney,and brain function.Objective:The aim of thi... Heavy metal contaminated water sources pose serious health risks for humans,animals,and plants.Exposure to and ingestion of heavy metals have been associated to liver,kidney,and brain function.Objective:The aim of this research is to comparatively examine the metal removal efficacy of three solid bidentate chemicals and four plant materials.Study Design&Methods:Standard solutions of zinc(II)and lead(II)ions with concentrations of 1,000 ppm were respectively treated with OA(Oxalic Acid),dibasic bidentate ligands(sodium hydrogen phosphate and sodium carbonate).Then,the solutions were placed on a shaker for 15 h,centrifuged,and the supernatant was analyzed using ICP-AES(Inductively Coupled Plasma-Atomic Emission Spectrometry).Results:All the solid bidentate adsorbents were very effective in removing zinc and lead(>90%).However,more lead than zinc was removed across all adsorbents except for lemon where equal percent of zinc and lead(49%)were removed.OA and Na2HPO4 removed about equal amount of lead(>99%).The plant materials(SP(Spinach),bell pepper and GBP(Green Bell Pepper)),respectively and preferentially removed more lead(98.9%,98.3%,81.5%)than zinc(91.7%,46%,46%).Conclusion:Although plant materials have gained attraction for the remediation of heavy metal,however,some bidentate chemical ligands such as OA,sodium carbonate and sodium hydrogen phosphates are even more effective in removing these metals from contaminated water.Furthermore,heavier metals are preferentially removed than lighter metals. 展开更多
关键词 Organic acids OA REMEDIATION CHELATION ligandS heavy metal contamination
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4-Amino-1,2,4-triazole Resin-supported Palladium Complex as Phosphine-free Catalyst for Suzuki Reaction in Aqueous Phase
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作者 WU Xiang-mei WANG Yan GUO Sheng-rong 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2010年第2期331-334,共4页
1 Introduction The Suzuki cross-coupling reaction is a powerful and versatile method for the generation of unsymmetrical biaryls from arylboronic acids and aryl halides in a single step. However, the reaction is usua... 1 Introduction The Suzuki cross-coupling reaction is a powerful and versatile method for the generation of unsymmetrical biaryls from arylboronic acids and aryl halides in a single step. However, the reaction is usually performed in the presence of Pd catalyst along with phosphine ligand, which sometimes creates practical problems because organophosphines tend to be expensive, poisonous, and air sensitive. Recently, phos-phine-free ligands, 展开更多
关键词 Suzuki reaction phosphine-free ligand PALLADIUM 4-Amino-1 2 4-triazole resin
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D301 resin as a solid base for phosphine-free Heck reactions with heteroaryl halides 被引量:1
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作者 Wen Pei Xiang Mei Wu 《Chinese Chemical Letters》 SCIE CAS CSCD 2008年第4期399-402,共4页
A new and practical method of the D301 resin,a weak basic anion exchange resin with secondary amine functionality(Grade Matrix Structure:Styrene-DVB D301R),used as base to Heck reactions catalyzed by palladium reag... A new and practical method of the D301 resin,a weak basic anion exchange resin with secondary amine functionality(Grade Matrix Structure:Styrene-DVB D301R),used as base to Heck reactions catalyzed by palladium reagent without phosphine compound as ligand is described.It was found that the D301 resin used as base is an efficient and reusable base and can be regenerated and recycled in the reaction.The olefmation of heteroaryl halides prepared the corresponding products in good yields using D301 resin as base. 展开更多
关键词 Hock reaction PALLADIUM phosphine-free catalysts D301 resin
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Phosphine-free synthesis of FeTe2 nanoparticles and self-assembly into tree-like nanoarchitectures
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作者 Hongyu Wang Min Wu +3 位作者 Yixuan Wang Hao Wang Xiaoli Huang Xinyi Yang 《Chinese Physics B》 SCIE EI CAS CSCD 2019年第10期473-477,共5页
Manipulating the self-assembly of transition metal telluride nanocrystals(NCs) creates opportunities for exploring new properties and device applications. Iron ditelluride(FeTe2) has recently emerged as a new class of... Manipulating the self-assembly of transition metal telluride nanocrystals(NCs) creates opportunities for exploring new properties and device applications. Iron ditelluride(FeTe2) has recently emerged as a new class of magnetic semiconductor with three-dimensional(3D) magnetic ordering and narrow band gap structure, yet the self-assembly of FeTe2 NCs has not been achieved. Herein, the tree-like FeTe2 nanoarchitectures with orthorhombic crystal structure have been successfully synthesized by hot-injection solvent thermal approach using phosphine-free Te precursor. The morphology, size, and crystal structure have been investigated using transmission electron microscopy(TEM), high-resolution TEM(HRTEM),and powder x-ray diffraction(XRD). We study the formation process of tree-like FeTe2 NCs according to trace the change of the sample morphology with the reaction time. It was found that the FeTe2 nanoparticles show oriented aggregation and self-assembly behavior with the increase of reaction time, which is attributed to size-dependent magnetism properties of the samples. The magnetic interaction is thought to be the driving force of nanoparticle self-organization. 展开更多
关键词 SELF-ASSEMBLY transition metal TELLURIDES phosphine-free Te precursor tree-like NANOARCHITECTURES
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Unraveling structure and performance of protein a ligands at liquid–solid interfaces: A multi-techniques analysis 被引量:1
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作者 Yi Shen Xinshuang Chu Qinghong Shi 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第2期232-239,共8页
Oriented ligand immobilization is one of the most effective strategies used in the design and construction of a high-capacity protein A chromatography. In this work, cysteine was introduced as anchoring sites by subst... Oriented ligand immobilization is one of the most effective strategies used in the design and construction of a high-capacity protein A chromatography. In this work, cysteine was introduced as anchoring sites by substituting a specific residue on Helix Ⅰ, Ⅱ, and at C-terminus of antibody binding domain Z from protein A, respectively, to investigate structural evolution and binding behavior of protein A ligands at liquid-solid interfaces. Among the three affinity dextran-coated Fe_(3)O_(4) magnetic nanoparticles(Fe_(3)O_(4)@Dx MNPs), affinity MNPs with the immobilized ligand via N11C on Helix Ⅰ(Fe_(3)O_(4)@Dx-Z_(1) MNPs) had the highest helical content, and MNPs with the immobilized ligand via G29C on Helix Ⅱ(Fe_(3)O_(4)@Dx-Z_(2) MNPs) had the lowest helical content at the same pHs. It was attributed to less electrostatic attraction of ligand to negatively charged surface on Fe_(3)O_(4)@Dx-Z_(1) MNPs because of less positive charged residues on Helix Ⅰ(K6) than Helix Ⅱ(R27/K35). Among the three affinity MNPs, moreover, the highest affinity to immunoglobulin G(IgG) binding was observed on Fe_(3)O_(4)@Dx-Z_(1) MNPs in isothermal titration calorimetry measurement, further validating greater structural integrity of the ligand on Fe_(3)O_(4)@Dx-Z_(1) MNPs. Finally,the study of IgG binding on MNPs and 96-well plates showed that anchoring sites for ligand immobilization had distinct influences on IgG binding and IgG-mediated antigen binding. This work illustrated that anchoring sites of the ligands had a striking significance for the molecular structure of the ligand at liquid-solid interfaces and raised an important implication for the design and optimization of protein A chromatography and protein A-based immunoassay analysis. 展开更多
关键词 ADSORPTION Interface THERMODYNAMICS Protein A ligand IMMOBILIZATION Molecular structure
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Controllably partial removal of thiolate ligands from unsupported Au_(25) nanoclusters by rapid thermal treatments for electrochemical CO_(2)reduction 被引量:2
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作者 Liting Huang Yongfeng Lun +4 位作者 Yuping Liu Liming Chen Bowen Li Shuqin Song Yi Wang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第11期16-22,I0002,共8页
Colloidal synthesis of metal nanoclusters will inevitably lead to the blockage of catalytically active sites by organic ligands.Here,taking[Au_(25)(PET)_(18)]-(PET=2-phenylethanethiol)nanocluster as a model catalyst,t... Colloidal synthesis of metal nanoclusters will inevitably lead to the blockage of catalytically active sites by organic ligands.Here,taking[Au_(25)(PET)_(18)]-(PET=2-phenylethanethiol)nanocluster as a model catalyst,this work reports a feasible procedure to achieve the controllably partial removal of thiolate ligands from unsupported[Au_(25)(PET)_(18)]-nanoclusters with the preservation of the core structure.This procedure shortens the processing duration by rapid heating and cooling on the basis of traditional annealing treatment,avoiding the reconfiguration or agglomeration of Au_(25)nanoclusters,where the degree of dethiolation can be regulated by the control of duration.This work finds that a moderate degree of dethiolation can expose the Au active sites while maintaining the suppression of the competing hydrogen evolution reaction.Consequently,the activity and selectivity towards CO formation in electrochemical CO_(2)reduction reaction of Au_(25)nanoclusters can be promoted.This work provides a new approach for the removal of thiolate ligands from atomically precise gold nanoclusters. 展开更多
关键词 Gold nanoclusters THIOLATES ligand removal Electrochemically active surface area Electrochemical CO_(2)reduction
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A fast and in-depth self-reconstruction of anion ligands optimized CoFe-based pre-catalysts for water oxidation 被引量:1
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作者 Qiuyan Jin Hao Cui Chengxin Wang 《Green Energy & Environment》 SCIE EI CAS CSCD 2023年第3期812-819,共8页
The design of efficient and robust non-precious metal electrocatalysts towards oxygen evolution reaction(OER)is of great value for developing green energy technologies.The in-situ formed high-valence(oxy)hydroxides sp... The design of efficient and robust non-precious metal electrocatalysts towards oxygen evolution reaction(OER)is of great value for developing green energy technologies.The in-situ formed high-valence(oxy)hydroxides species during the reconstruction process of pre-catalysts are recognized as the real contributing sites for OER.However,pre-catalysts generally undergo a slow and inadequate self-reconstruction.Herein,we reported a PO^(3-)_(4)optimized CoFe-based OER catalysts with amorphous structure,which enables a fast and deep reconstruction during the OER process.The amorphous structure induced by ligands PO^(3-)_(4)is prone to evolution and further form active species for OER.The electron interaction between metal sites can be modulated by electron-rich PO^(3-)_(4),which promotes generation of high active CoOOH.Simultaneously,the etching of PO^(3-)_(4)from the pre-catalysts during the catalytic process is in favor of accelerating the self-reconstruction.As a result,as-prepared precatalyst can generate high active CoOOH at a low potential of 1.4 V and achieve an in-depth reconstructed nanosheet structure with abundant OER active sites.Our work provides a promising design of pre-catalysts for realizing efficient catalysis of water oxidation. 展开更多
关键词 Oxygen evolution reaction Pre-catalysts Reconstruction Anion ligands Bimetallic catalysts
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Metal-organic frameworks with mixed-ligands strategy as heterogeneous nucleation center to assist crystallization for efficient and stable perovskite solar cells 被引量:1
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作者 Yayu Dong Shuang Gai +9 位作者 Jian Zhang Ruiqing Fan Boyuan Hu Wei Wang Wei Cao Jiaqi Wang Ke Zhu Debin Xia Lin Geng Yulin Yang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第2期1-10,I0001,共11页
Deep-level defects and random oriented configuration in perovskite crystallization process would cause the nonradiative recombination and further affect the performance of perovskite solar cells(PSCs).Herein,two metal... Deep-level defects and random oriented configuration in perovskite crystallization process would cause the nonradiative recombination and further affect the performance of perovskite solar cells(PSCs).Herein,two metal-organic frameworks(MOFs)with tunable Lewis-base passivation sites have been constructed(Cd-Httb and Cd-Httb-BDC,Httb=5-(4-(1H-1,2,4-triazole-1-yl)benzyl)-1h-tetrazole,BDC=1,4-dicarboxybenzene)to eliminate deep-level defects and simultaneously as nanostructured heterogeneous nucleation seed to assist the growth of large-grained perovskite films.Compared with the control and Cd-Httb,Cd-Httb-BDC designed with mix-ligands strategy exhibited the enhanced inducted effect on the crystallization and nucleation of high-quality perovskite films during annealing process.Consequently,the resultant Cd-Httb-BDC-modified device achieved higher power conversion efficiency(PCE)(22.18%)than the control(20.89%)and Cd-Httb(21.56%).Meanwhile,the unencapsulated Cd-Httb-BDC-modified device still maintained 90%of initial PCE after 1500 h in ambient conditions and exhibited enhanced thermal stability(85℃ in N_(2) atmosphere).This work presented a successful example of mixligands strategy on construction of high-quality MOF-assisted perovskite films for high-efficient and stable PSCs. 展开更多
关键词 Perovskite solar cells Metal organic frameworks Mixed ligands strategy Passivation Stability
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In Silico Evaluation of Potential Ligands of Cancer Cells for Surfactin from Bacillus spp. 被引量:1
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作者 Mahmuda Akhter Akhi Umme Tamanna Ferdous +2 位作者 Md.Fakruddin Suvamoy Datta Md.Asaduzzaman Shishir 《Proceedings of Anticancer Research》 2023年第3期18-28,共11页
Cancer is one of the most prevalent diseases worldwide,which causes significant morbidity and mortality.Designing and developing a potential anti-cancer drug is an active field of research worldwide.Microorganisms hav... Cancer is one of the most prevalent diseases worldwide,which causes significant morbidity and mortality.Designing and developing a potential anti-cancer drug is an active field of research worldwide.Microorganisms have been considered a potential source of anti-cancer drugs.One such microbe-derived compound is surfactin,which shows potential anti-cancer activities.In this study,we evaluated the binding potential of surfactin with several cancer cell ligands via an in-silico approach.Hence,molecular docking studies were performed to test the binding potential of surfactin against four targets.The analyses revealed that surfactin from Bacillus sp.can bind with the targeted ligands(coenzyme A,D-leucine,glycerol,and(R)-3-hydroxytetradecanal)with significant affinity.Surfactin showed the highest binding affinity(-7.7 kcal mol-1)to coenzyme A among the targeted ligands.These results may be useful for developing anti-cancer drugs.Nevertheless,further experimental studies are needed to investigate the ligand binding capacity and anti-cancer potential of such surfactin-like molecules. 展开更多
关键词 Molecular docking CANCER ligand SURFACTIN BACILLUS
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Engineering of Ag@Pd/Al_(2)O_(3)with varied Pd-shell thickness:Dynamic evolution of ligand and strain effects on acetylene selective hydrogenation
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作者 Mingbo Yang Tianxing Yang +3 位作者 Rui Ma Sha Li Yufei He Dianqing Li 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第12期139-148,共10页
Bimetallic nanoparticles exhibit a synergistic effect that critically depends on their surface composition,but such promotion mechanisms become vague with varying surface compositions.Here,alumina supported Ag@Pd core... Bimetallic nanoparticles exhibit a synergistic effect that critically depends on their surface composition,but such promotion mechanisms become vague with varying surface compositions.Here,alumina supported Ag@Pd core–shell and PdAg alloy structure with controlled size and surface compositions were prepared to demonstrate synergetic mechanisms,particularly,ligand and strain effects on activity and ethylene selectivity for acetylene hydrogenation.The performance evaluation indicates that Ag@Pd catalysts with well-controlled Pd-shell thickness can effectively lower apparent activation energy and improve ethylene selectivity.Hydrogenation activity increases from 0.019 to 0.062 s^(-1) with decreasing Pd-shell thickness under mild conditions,which is 3–6 times higher than their alloyed and monometallic counterparts.Combined characterizations and density functional theory are conducted to reveal such shell-thickness-dependent performance.The ligand effect arising from Ag alloying in the interface of Ag@Pd2ML observes the strongest binding of acetylene,but it diminished sharply and the strain effect gets more prevailing with increasing shell thickness.The competition of ethylene desorption and deephydrogenation were also investigated to understand the selectivity governing factors,and the selectivity descriptor(0.5BE(C_(2)H_(4))–BE(H))was built to match the contribution of ligand and strain effect on the different surfaces of Pd-Ag bimetallic NPs.The exploration of synergetic mechanisms among bimetallic NPs with varied structure and surface compositions in this work can help us to deepen the understanding catalyst structure–activity relationship and provide a feasible way to optimize the overall catalytic performance. 展开更多
关键词 Catalyst HYDROGENATION NANOSTRUCTURE Shell-thickness-dependent performance ligand and strain effect
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